US4857381A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Reinforced dielectric sheet
Assignee: Junkosha Co Ltd
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Filing: 1988-05-05
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Granted: 1989-08-15
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Expires: 2008-05-05
Abstract
Abstract A reinforced porous dielectric sheet of expanded polytetrafluoroethylene is provided wherein solid plastic reinforcement elements in the form of circular columns or wall-like partitions extending through the dielectric sheet from one surface to the other are distributed within the sheet. The reinforced sheet is useful as a substrate for printed circuit boards. The reinforcement elements are preferably of a tetrafluoroethylene/ethylene copolymer or an epoxy resin.
Inventors
- 👤 Hirosuke Suzuki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 08:41
CPC Classifications
H; H05; H05K; H05K1/00; H05K1/02; H05K1/03; H05K1/0313; H05K1/0353; B; B29; B29C; B29C70/00; H05K1/0271; H05K2201/00; H05K2201/01; H05K2201/0104; H05K2201/0116; H05K2201/0137; H05K2201/015; H05K2201/0183; H05K2201/0187; H05K2201/20; H05K2201/2009; Y; Y10; Y10S; Y10S428/00; Y10S428/901; Y10T; Y10T428/00; Y10T428/24; Y10T428/24174; Y10T428/24182; Y10T428/24802; Y10T428/249921; Y10T428/249953; Y10T428/249987; Y10T428/249991; Y10T428/31504; Y10T428/31511; Y10T428/3154; Y10T428/31544
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
59 words
A reinforced porous dielectric sheet comprising a porous dielectric sheet of expanded, porous polytetrafluoroethylene having at least three solid reinforcement elements of another plastic extending through said dielectric sheet from one surface to the other, said reinforcement elements being distributed within the sheet, wherein said other plastic is selected from the class consisting of tetrafluoroethylene/ethylene copolymer and epoxy resin.
Claim 2
Dependent Claim
59 words
A reinforced porous dielectric sheet comprising a porous dielectric sheet of expanded, porous polytetrafluoroethylene having at least three solid reinforcement elements of another plastic extending through said dielectric sheet from one surface to the other, said reinforcement elements being distributed within the sheet, wherein said other plastic is selected from the class consisting of tetrafluoroethylene/ethylene copolymer and epoxy resin.
Claim 3
Dependent Claim
19 words
The reinforced porous dielectric sheet of claim 1 wherein said reinforcement elements are in the form of circular columns.
Claim 4
Dependent Claim
19 words
The reinforced porous dielectric sheet of claim 1 wherein said reinforcement elements are in the form of wall-like partitions.
Claim 5
Dependent Claim
16 words
The reinforced porous dielectric sheet of claim 1 as the substrate for a printed circuit board.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-08-14 | 1993-02-13 | 1993-08-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-08-14 | 1997-02-13 | 1997-08-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-08-14 | 2001-02-13 | 2001-08-15 | $7700.00 | Window Closed / Lapsed |